350 using oil

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Marcus

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So the 350 I have to put in my truck is using oil. When I removed the manifolds to put a different set on it, the bolts all had oil on them and oil was coming out of a couple of holes as well as inside the exhaust holes being dirty as can be except one or two. It’s probably leaking in one or more spots as well but I cannot afford a total rebuild like it actually needs. What do I need to replace to stop the oil from coming out of the exhaust bolt holes? I plan to replace oil pan gasket, rear main seal, and also the valve cover gaskets. Thanks for the help in advance.

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dvdswan

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I may be wrong, but I don't recall exhaust bolts near any where oil is in the heads. Exhaust ports look relatively clean. I would try and swap the heads because the old ones are probably cracked. I don't think valve cover leaking would get in the exhaust bolts and look like that.

Again, I could be wrong.
 

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I may be wrong, but I don't recall exhaust bolts near any where oil is in the heads. Exhaust ports look relatively clean. I would try and swap the heads because the old ones are probably cracked. I don't think valve cover leaking would get in the exhaust bolts and look like that.

Again, I could be wrong.

Look at the block inthe pic it is covered with oil/dirt. My bet is the valve cover leaked onto the bolts and then weeped its way down the bolts.
 

dvdswan

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That looks like a bit of oil just to weep though. Yes the head is covered with oil from the valve cover but 6 of 8 holes, that must of had a good exhaust manifold leak.
 

bucket

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I agree, a badly leaking valve cover gasket can let oil seep into the threads of the manifold bolts. It accumulates over time and has nowhere to go. It can seep into the spark plug threads too.
 

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I agree, a badly leaking valve cover gasket can let oil seep into the threads of the manifold bolts. It accumulates over time and has nowhere to go. It can seep into the spark plug threads too.



See my grandpa said that it was fouling out plugs a lot but he also said that they were gas fouled and not oil fouled but I have a hard time believing that because of all the oil everywhere. It’s all over the entire engine.

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4WDKC

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That looks like a bit of oil just to weep though. Yes the head is covered with oil from the valve cover but 6 of 8 holes, that must of had a good exhaust manifold leak.

but over how many hours/miles of heat cycles and vibration? The other option is the head cracked at each hole for the manifold and allowed oil to leak in without becoming loose and causing an exhaust leak or falling out. Which seems more likely?
 

dvdswan

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Get some engine degreaser, cover all open ports, then spray degreaser and spray off with HP sprayer. Buy intake, valve covers, timing cover, and oil pan gaskets and reseal it and replace the plugs.

I do know that intake, timing cover, and valve cover oil leaks can cover an engine in grime.

As @bucket said it will get into the spark plugs, I've just never seen it in the exhaust bolts.
 

4WDKC

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So the 350 I have to put in my truck is using oil. When I removed the manifolds to put a different set on it, the bolts all had oil on them and oil was coming out of a couple of holes as well as inside the exhaust holes being dirty as can be except one or two. It’s probably leaking in one or more spots as well but I cannot afford a total rebuild like it actually needs. What do I need to replace to stop the oil from coming out of the exhaust bolt holes? I plan to replace oil pan gasket, rear main seal, and also the valve cover gaskets. Thanks for the help in advance.

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Honestly if it needs rebuilt that bad why put the moeny into sealing it when you could use the money to find one thats ready to drop in?
 

Marcus

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Honestly if it needs rebuilt that bad why put the moeny into sealing it when you could use the money to find one thats ready to drop in?


I’m unemployed and don’t have income so working on very minimum budget. It’s the only vehicle I have right now because the trans literally blew up in the car I had and it was gonna cost way more than the car was worth to fix it so I sold it. Just trying to get something going for now.
 

Marcus

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but over how many hours/miles of heat cycles and vibration? The other option is the head cracked at each hole for the manifold and allowed oil to leak in without becoming loose and causing an exhaust leak or falling out. Which seems more likely?


Used to be in a 81 Jimmy that was customized farm style for a feed/hay truck. Was never ran more than 25mph for several years. Ran 10-15mph tops most days. Also the person who put it in the Jimmy originally didn’t put gaskets on manifolds either so there’s that. The manifold that was on the passenger side had a pretty good crack in it.
 

dvdswan

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Honestly if it needs rebuilt that bad why put the moeny into sealing it when you could use the money to find one thats ready to drop in?

Agree, there's no telling how many miles are on that engine. But as he said limited budget, you can only do so much.

If you've got the tools, or you can rent/borrow them at autozone and such, do a compression test on the cylinders to see if its worth the time.

edit:
the plot starts to thicken.
 

Marcus

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Agree, there's no telling how many miles are on that engine. But as he said limited budget, you can only do so much.

If you've got the tools, or you can rent/borrow them at autozone and such, do a compression test on the cylinders to see if its worth the time.

edit:
the plot starts to thicken.



I’ve got some tools and access to plenty of tools. I’ve thought about compression test but at the same time, I don’t have any other options for a vehicle so right now I have to use this engine until I can buy a vehicle and start redoing this engine/truck.
 

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On the bright side...you probably won't have to buy any PB Blaster during teardown?
 

Marcus

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On the bright side...you probably won't have to buy any PB Blaster during teardown?


You’re probably right cause the transmission bolts were easier than they should have been.
 

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